CN1816590A - Silane formulations with high filler content - Google Patents

Abstract

The present invention relates to a formulation comprising the following components: (i) at least one organoalkoxysilane and/or at least one organoalkoxysiloxane, (ii) at least one inorganic oxide powder, and (iii) if desired, an organic or inorganic acid, component (ii) comprising 5 to 50% by weight of the formulation and having a viscosity of less than 1500 mPa·s. The invention also relates to a method for preparing such a formulation and to its use.

Description

Silane formulations with high filler content

The present invention relates to new formulations comprising organoalkoxysilanes and a high proportion of inorganic oxide powders, their preparation and their use.

In many chemical products, inorganic oxide powders are used as pigments for coloring purposes and as fillers. Examples include fumed silica or the corresponding titania or alumina, precipitated alumina or alumina hydroxide or aluminum hydroxide, precipitated silica, iron oxide, zirconia and other metal oxides. The powders are used, for example, in the production of plastics and paints and inks. The problem here is that the powder particles should be distributed as evenly as possible into the product. Silanes are also frequently used in the preparation of such products. Powders whose surface has been modified with silanes can also be used. Furthermore, the uniformity of ion distribution can have a substantial impact on the quality of particularly good products. Incorporation of powder fractions into compositions is often difficult and laborious in terms of equipment, especially when the particles are very fine.

It is an object of the present invention to provide an additional method for the incorporation of inorganic oxide powders having a size down to the nanometer range into alkoxysilanes.

This object is achieved according to the invention as described in the claims.

Surprisingly, it has been found that nanoscale inorganic oxide powders (an example of which) can be mixed by a sufficient dispersing operation, including the addition of less than 0.8 mol, preferably less than 0.5 mol of water per mole of silicon in the silane and/or siloxane used. including hydrophilic and hydrophobic fumed silica, fumed alumina, boehmite and titanium dioxide), especially in larger quantities, uniformly, simply and economically and at the same time relatively advantageously blended into In organoalkoxysilanes of the general formula I and/or in organoalkoxysiloxanes of the general formula II, the viscosity of the system according to the invention compares with the viscosity of the formulation in which the powder is simply stirred into the silane and/or siloxane Significantly lower. In the preparation of the system according to the invention, it is also possible to add catalytic amounts of organic or inorganic acids and wetting assistants. A further reduction in the viscosity of the system according to the invention can be achieved if it is treated with ultrasound during its preparation or subsequently.

The systems obtained in this way are generally clear, transparent to opalescent, easily pourable liquids of relatively low viscosity and hitherto unknown very high solids content.

Furthermore, the preparations according to the invention can advantageously be diluted with organic solvents or solvent mixtures, for example alcohols or esters, as required.

In addition, the system of the present invention is essentially a storage stable liquid, which generally has a storage stability of 6-12 months at room temperature.

The systems according to the invention are referred to below in particular as highly filled silane formulations or simply silane formulations or formulations.

The silane preparations according to the invention can advantageously be used as so-called liquid powders, especially if organosilanes and/or organosiloxanes can also be added.

The highly filled silane formulations according to the invention can be used simply and advantageously, especially in downstream products, examples being other kinds of liquid systems, such as solutions, mixtures or melts; Compared to systems of the invention, the systems of the invention can be blended relatively effortlessly, quickly and with exceptional homogeneity.

The use of the silane formulations according to the invention is also particularly advantageous, since the silanes acting as solvents still contain a sufficient number of hydrolyzable alkoxy groups which, after further hydrolysis, are able to participate in condensation reactions with silanes or organic OH-functional components when the network forms When the organic oxide particles are incorporated into the network.

Accordingly, the present invention provides formulations comprising (i) at least one organoalkoxysilane and/or at least one organoalkoxysiloxane, and (ii) at least one inorganic oxide powder, and (iii) if desired, organic or inorganic acids, wherein component (ii) constitutes 5-50% by weight of the formulation, preferably 10-35% by weight, more preferably 15-32% by weight, and very preferably 20-30% by weight % by weight, and the formulation has a viscosity of less than 1500 mPa·s, preferably 10-800 mPa·s, particularly preferably 50-500 mPa·s, very preferably 100-450 mPa·s.

The formulations according to the invention may comprise wetting assistants as further component (iv). Wetting aids which can be used include the customary surface-active substances, especially nonylphenol polyglycol ethers, examples being the Marlophen ^(R) product range from Sasol.

The formulations according to the invention may additionally comprise as component (v) diluents or solvents, for example alcohols, suitably methanol or ethanol, and, if desired, water.

The preparations according to the invention preferably comprise as component (i) at least one organoalkoxysilane of the general formula (I)

R _a -Si(OR ¹ ) _4-a (I),

wherein R are the same or different, and are straight chains with 1-18 carbon atoms,

Cyclic, branched or optionally substituted alkyl, preferably methyl, n-propyl or octyl, or alkenyl with 2 to 8 carbon atoms, preferably vinyl, or aryl, preferably phenyl, or propene Acyloxyalkyl or methacryloxyalkyl, preferably 3-methacryloxypropyl, or glycidyloxyalkyl, such as 3-glycidyloxypropyl, or partly fluorine Fluorinated or perfluorinated fluoroalkyl groups, such as tridecafluoro-1,1,2,2-tetrahydrooctyl, or aminoalkyl groups, such as 3-aminopropyl-, N-n-butyl-3-amino Propyl or N-(2-aminoethyl)-3-aminopropyl or corresponding monosilylated or hyposilylated aminoalkyl groups, or alkoxy groups having 1 to 6 carbon atoms, for example Methoxy, ethoxy, propoxy or 2-methoxyethoxy, or ureidoalkyl, or epoxyalkyl, or mercaptoalkyl having 1 to 6 carbon atoms in the alkyl group, Such as 3-mercaptopropyl, or silylated alkylsulfanyl, such as bis[3-(triethoxysilyl)propyl]tetrasulfanyl, or thiocyanoalkyl, or iso Cyanatoalkyl, ^R is straight chain, cyclic or straight chain alkyl with 1-6 carbon atoms, preferably methyl, ethyl or n-propyl or isopropyl, a is 0 or 1 or 2 ,

and/or at least one organoalkoxysiloxane of general formula (II)

${\mathrm{<span\; class="notranslate">\; R</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}{{\mathrm{<span\; class="notranslate">\; R</span>}}^{\mathrm{<span\; class="notranslate">\; 3</span>}}}_{\mathrm{<span\; class="notranslate">\; x</span>}}{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; R</span>}}^{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; o</span>}<span\; class="notranslate">\; )</span>}_{\mathrm{<span\; class="notranslate">\; the\; y</span>}}\mathrm{<span\; class="notranslate">\; Si</span>}{\mathrm{<span\; class="notranslate">\; o</span>}}_{\frac{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; II</span>}<span\; class="notranslate">\; )</span>$

Wherein the group R ² is the same or different, and R ² is a linear, cyclic, branched or substituted alkyl group with 1-18 carbon atoms, an alkenyl group with 2-8 carbon atoms, an aryl acryloxyalkyl or methacryloxyalkyl, glycidyloxyalkyl, epoxyalkyl, fluoroalkyl, aminoalkyl, silylated aminoalkyl, ureidoalkyl mercaptoalkyl group having 1-6 carbon atoms in the alkyl group, silylated alkylsulfanyl group, thiocyanatoalkyl group, isocyanatoalkyl group or alkane group having 1-6 carbon atoms Oxygen group, R ³ is a straight chain, cyclic, branched or substituted alkyl group with 1-18 carbon atoms, R ⁴ is a straight chain, cyclic or branched chain alkyl group with 1-6 carbon atoms, x is 0 or 1 or 2, and y is 0 or 1 or 2, provided that (x+y)<3.

Furthermore, the formulations according to the invention preferably comprise at least one nanoscale powder (ii) having an average particle size (d ₅₀ ) of less than 1200 nm, preferably 50-1000 nm, more preferably 100-900 nm, very preferably 200-800 nm , such powders are preferably selected from silicon oxides, such as ^Aerosil® , aluminum oxides, such as aluminum oxide C, and titanium oxides. The fineness of the grinding, as determined with a fineness meter according to DIN EN ISO 1524, is generally <10 μm. The particle size distribution can be determined by laser diffraction.

In addition, preparations according to the invention may comprise at least one reaction product of components (i) and (ii) as further components, in which case, according to the model concept, component (i) or, if appropriate, partially hydrolyzed Component (i) can react with reactive centers such as hydroxyl groups on the surface of powder (ii) while eliminating alcohol molecules or water molecules.

According to DIN/ISO 3251 "Determination of the non-volatile fraction of varnishes, paints and binders for varnishes and paints" (suitably at 125° C. in a drying cabinet for 1 hour), the formulations according to the invention can advantageously have a % by weight, preferably up to 80% by weight, very preferably up to 60% by weight, of the solids content, based on the weight of the preparation, the individual components of the preparation amounting to 100% by weight.

The present invention also provides a process for the preparation of a formulation having a low viscosity despite a high solids content, the process comprising

- mixing components (i), (ii) and if necessary (iv),

- Addition of 0.001 to <0.8 mol water/mol silicon in component (i), preferably 0.05-0.5 mol water/mol silicon in component (i), more preferably 0.1-0.4 mol water/mol component (i) Silicon in, very preferably 0.2-0.35 mol of water per mole of silicon in component (i), if desired together with a catalytic amount of organic or inorganic acid according to component (iii), and

- Disperse the mixture well.

As organoalkoxysilanes of the general formula (I), methyltriethoxysilane, methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane are preferably used , Vinyltriethoxysilane, Vinyltrimethoxysilane, 3-Methacryloxypropyltrimethoxysilane, 3-Methacryloxypropyltriethoxysilane , 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, tridecafluoro-1,1,2,2-tetrahydrooctyltrimethoxy Trideoxysilane, tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-(n-butyl)-3-aminopropyl N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane Silane, bis(3-trimethoxysilylpropyl)amine, 3-mercaptopropyltrimethoxysilane, or at least one organoalkoxysiloxane of general formula (II), or selected from amino Organoalkoxysiloxanes of silanes and mixtures with alkylsilanes and/or organofunctional silanes according to DE 101 51 264, 3-methacryloxypropyltrimethoxysilane and mixtures according to DE 198 34 990 Mixtures of alkylsilanes etc., mixtures of alkylsilanes with alkylsilanes according to EP 0 978 525 A2 or EP 0 814 110 A1, especially methyltrialkoxysilane with propyltrialkoxysilane or phenyl Mixtures of trialkoxysilanes and mixtures of vinylalkoxysilanes with alkylalkoxysilanes according to EPO 0 518 057 A1, the alkoxy groups being preferably methoxy or ethoxy, or the general formula (I) A mixture of organoalkoxysilanes and organoalkoxysiloxanes of general formula (II).

In the process according to the invention, preference is given to using as component (ii) nanoscale powders selected from the group consisting of silicon oxides, such as fumed silica, precipitated silica, silicates, aluminum silicates, aluminum oxides, including Aluminum oxide hydroxide or aluminum hydroxide, transition metal oxides, such as titanium oxide, metatitanic acid, iron oxide, zinc oxide, copper oxide, chromium oxide, or mixtures thereof, the powder according to (ii) preferably has 50- BET surface area of 400 m ² /g. By way of example but not to the exclusion of others, silica such as Aerosil® ³⁸⁰ from Degussa, preferably having a BET surface area of 380 m ² /g, alumina such as boehmite Disperal® from Sasol Germany GmbH may be used in the process of the invention. ^® P3, preferably with a BET surface area of 300 m ² /g, alumina C from Degussa, preferably with a BET surface area of 100 m ² /g, and titanium dioxide, for example RM 300 from Sachtleben, preferably with a BET of 80 m ² /g surface area.

In the process of the invention, components (i) and (ii) are suitably used in a weight ratio of 19:1 to 1:1, preferably 10:1 to 3:2.

As component (iii), organic or inorganic acids are preferred, preferably hydrogen chloride, for example in the form of aqueous or concentrated hydrochloric acid, or formic acid, acetic acid, acrylic acid, maleic acid or other suitable organic acids, said acids being present in the form of 10- It is present in an amount of 3500 ppm by weight, preferably 100-1000 ppm by weight, more preferably 200-400 ppm by weight, based on the amount of component (i) in the formulation.

The process according to the invention is preferably carried out in a dispersion plant. Preference is given to using dispersing equipment with good shear action. On a laboratory scale, for example dissolvers of the type Dispermat CV or Ultra-Turrax T 25 can be used.

The components used are preferably dispersed at a temperature of 0-80°C, preferably 10-60°C, for 10-60 minutes, more preferably 15-40 minutes.

The dispersion or preparation obtained in this way can be worked up by stirring at a temperature of 30-80° C. for 1-8 hours, preferably 2-6 hours.

The preparations according to the invention can be adjusted to pH 2-7, preferably pH 3-5, by adding organic or inorganic acids. According to the invention, in the case of aminosilanes, the pH is generally determined by the nature of the aminosilane used and is generally in the alkaline range, although the formulation can of course be made neutral or acidic by adding an acid.

The invention also provides formulations obtainable by the methods of the invention.

According to the invention, formulations according to the invention or suitable dilutions can be used for anti-scratch applications, anti-wear applications, anti-corrosion applications, easy-to-clean applications, barrier applications, in electronic subsections, for surface treatment of circuit boards , used as an insulating layer, used as a release layer, used as a surface coating for solar cells, used as a glass fiber compound, and used to uniformly blend nanoscale powders into other types of systems.

Such formulations according to the invention can be used particularly advantageously in the production of plastics, adhesives, sealants, inks and paints, and in the synthesis of resin-based materials.

The present invention therefore also provides the use of the formulations according to the invention for synthetic resin-based materials or as components in plastics, adhesives, sealants, inks and paints, or as components in their preparation.

The invention also provides articles obtainable using the formulations of the invention.

Generally speaking, the inventive method can be carried out as follows:

Typically, components (i), (ii), (iii) and/or (iv) are combined with a pre-measured amount of water, and the mixture is dispersed to produce a uniform, free-flowing formulation. The preparations obtained in this way can also be diluted by adding component (v); that is to say, solvents or diluents can be added to the preparations according to the invention, preferably alcohols are given as component (v), for example methanol, ethanol, Isopropanol, Butanol, 2-Methoxypropanol, Diols such as Butyl Glycol, Propyl Glycol, Glycol Ethers, Aromatics such as Xylene, Toluene, Esters such as Ethyl Acetate, Butyl Acetate, Ketones For example methyl ethyl ketone, or mixtures thereof. Surprisingly, it is also possible to use water as diluent, especially when glycidyloxyalkylalkoxysilanes are used as component (i).

It has also been found that post-treatment of the formulations prepared by the process of the invention with an ultrasonic processor such as UP 200 S advantageously leads to a further reduction in viscosity and a further improvement in particle size.

The invention is illustrated by the following examples:

Example

Example 1

30% by weight ^Aerosil® 380 in ^DYNASYLAN® MTES

90.0 g of methyltriethoxysilane ( ^DYNASYLAN® MTES) was placed in a double jacketed 250 ml stainless steel dispersion vessel, and a solution of 2.7 g of deionized water and 0.05 g of concentrated hydrochloric acid was added with stirring (Dispermat CV). The liquid was stirred in the dissolver at a peripheral speed of 0.8 m/s for 5 minutes while cooling with water. This was followed by the initial addition of 40 g of nanoscale fumed silica ( ^Aerosil® 380). When 4-5% by weight of Aerosil was dispersed in the hydrolyzate, the viscosity increased significantly. During the further addition of Aerosil, the speed of the dissolver was gradually increased to a peripheral speed of about 8 m/s. The blending time was about 15 minutes. Immediately after complete addition of all Aerosil, dispersion was continued for 3 minutes at a peripheral speed of 25 m/s. During the dispersion operation the temperature was raised to 38°C. The liquid thus obtained was then stirred for a further 2 hours at 80°C.

This gives a yellowish opalescent liquid having a viscosity of approximately 400 mPa·s, measured at 20° C. (DIN 53015). A portion of the liquid was separated and post-treated for 3 minutes with an ultrasonic processor UP 200S, which resulted in a viscosity reduction of approximately 130 mPa·s (DIN 53015).

The product was stored at 50°C for 12 months, the system remained stable and no obvious precipitation was observed.

According to DIN/ISO 3251, the solids content of the resulting product was determined to be 40% by weight of the composition. The UV transmission graph (measured against air in a 1 cm quartz glass cuvette) indicated <2% transmission in the 200-250 nm region.

Example 2

20% by weight ^Aerosil® 380 in ^DYNASYLAN® VTMO

90.0 g of vinyltrimethoxysilane ( ^DYNASYLAN® VTMO) was placed in a 250 ml stainless steel dispersion vessel, and a solution of 3.3 g of deionized water and 0.05 g of concentrated hydrochloric acid was added under stirring (Dispermat CV). The liquid was stirred in the dissolver at a peripheral speed of 0.8 m/s for 5 minutes while cooling with water. This was followed by the initial addition of 31.2 g of nanoscale fumed silica ( ^Aerosil® 380). When 4-5% by weight of Aerosil was dispersed in the hydrolyzate, the viscosity increased significantly. During the further addition of Aerosil, the speed of the dissolver was gradually increased to a peripheral speed of about 8 m/s. The blending time is about 20 minutes. Immediately after complete addition of all ^Aerosil® , dispersion was continued for 3 minutes at a peripheral speed of 25 m/s. During the dispersion operation the temperature was raised to 41°C. The liquid thus obtained was subsequently stirred for a further 2 hours at 65°C.

This gives a clear, pale yellow liquid with a viscosity of <1000 mPa·s measured at 20° C. (DIN 53015). The product was stored at 50°C for 12 months, the system remained stable and no obvious precipitation was observed.

According to DIN/ISO 3251, the solids content of the resulting product was determined to be 42% by weight of the composition.

Example 3

30% by weight ^Aerosil® 380 in ^DYNASYLAN® MEMO

90.0 g of 3-methacryloxypropyltrimethoxysilane ( ^DYNASYLAN® MEMO) was placed in a 250 ml stainless steel dispersion vessel, and 2.0 g of deionized water and 0.3 g of acrylic acid and 0.3 g of acrylic acid were added under stirring (Dispermat CV). A solution of 10.0 g methanol. The liquid was stirred in the dissolver at a peripheral speed of 0.8 m/s for 5 minutes while cooling with water. This was followed by the initial addition of 43.5 g of nanoscale fumed silica ( ^Aerosil® 380). When 4-5% by weight of Aerosil was dispersed in the hydrolyzate, the viscosity increased significantly. During the further addition of Aerosil, the speed of the dissolver was gradually increased to a peripheral speed of about 8 m/s. Blending time was approximately 22 minutes. Immediately after complete addition of all ^Aerosil® , dispersion was continued for 3 minutes at a peripheral speed of 25 m/s. During the dispersion operation the temperature was raised to 35°C. The liquid thus obtained was then stirred for a further 2 hours at 64°C.

This gave a clear, colorless liquid. The product was stored at 50°C for 3 months, the system remained stable and no obvious precipitation was observed.

According to DIN/ISO 3251, the solids content of the resulting product was determined to be 80% by weight of the composition.

Example 4

20% by weight ^Aerosil® 380 in ^DYNASYLAN® DAMO

90.0 g of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane ( ^DYNASYLAN® DAMO) was placed in a 250 ml stainless steel dispersion vessel. While stirring (Dispermat CV) at a peripheral speed of 0.8 m/s and cooling with water, the addition of 23.0 g of nanoscale fumed silica ( ^Aerosil® 380) was started. When 4-5% by weight of Aerosil was dispersed in the hydrolyzate, the viscosity increased significantly. During the further addition of Aerosil, the speed of the dissolver was gradually increased to a peripheral speed of about 8 m/s. The blending time is about 10 minutes. Immediately after complete addition of all ^Aerosil® , dispersion was continued for 3 minutes at a peripheral speed of 25 m/s. During the dispersion operation the temperature was raised to 37°C.

This gives a clear, milky liquid. The product was stored at 50°C for 12 months, the system remained stable and no obvious precipitation was observed.

According to DIN/ISO 3251, the solids content of the resulting product was determined to be 81% by weight of the composition.

Example 5

17% by weight alumina C in ^DYNASYLAN® AMMO

90.0 g of 3-aminopropyltrimethoxysilane ( ^DYNASYLAN® AMMO) was placed in a 250 ml stainless steel dispersion vessel, and 7.2 g of deionized water was added under stirring (Dispermat CV). The liquid was stirred in the dissolver at a peripheral speed of 0.8 m/s for 5 minutes while cooling with water. This was followed by starting the addition of 23 g of nanoscale fumed alumina (Alumina C) at a peripheral speed of 0.8 m/s. When 4-5% by weight of alumina is dispersed in the hydrolyzate, the viscosity increases significantly. During the further addition of alumina, the speed of the dissolver was gradually increased to a peripheral speed of about 8 m/s. The blending time is about 10 minutes. Immediately after the complete addition of all the alumina, the dispersion was continued for 3 minutes at a peripheral speed of 25 m/s. During the dispersion operation the temperature was raised to 34°C.

This gives a milky white, opalescent liquid with a viscosity of <10000 mPa·s measured at 20° C. (DIN 53015). The product was stored at 50°C for 4 months, the system remained stable and no obvious precipitation was observed.

Example 6

26% by weight ^Aerosil® 380 in ^DYNASYLAN® 1189

400.0 g of N-(n-butyl)-3-aminopropyltrimethoxysilane ( ^DYNASYLAN® 1189) was placed in a 1 liter stainless steel dispersion vessel and 9.15 g of deionized water were added with stirring (Dispermat CV). The liquid was stirred in the dissolver at a peripheral speed of 0.8 m/s for 5 minutes while cooling with water. This is followed by the start of the addition of 127 g of nanoscale fumed silica ( ^Aerosil® ) at a peripheral speed of 0.8 m/s. When 4-5% by weight of Aerosil was dispersed in the hydrolyzate, the viscosity increased significantly. During the further addition of Aerosil, the speed of the dissolver was gradually increased to a peripheral speed of about 8 m/s. Blending time was approximately 45 minutes. Immediately after complete addition of all ^Aerosil® , dispersion was continued for 5 minutes at a peripheral speed of 25 m/s. The dispersion temperature was raised to 56°C. This gives a clear yellowish liquid.

Subsequently, 54 g of methanol liberated by hydrolysis were removed by evaporating the highly filled Silan- ^Aerosil® formulation in a rotary evaporator at a bath temperature of 60° C. and _Pabs =1 mbar. The free methanol content (GC) in the concentrated Silane- ^Aerosil formulation is <1%. The clear yellowish liquid has a viscosity of 309 mPa·s at 20° C. (DIN 53015).

The product was stored at 50°C for 2 months, during which time the system remained stable and no significant precipitation was observed.

Example 7

10% by weight titanium dioxide in ^DYNASYLAN® GLYMO

Put 400.0g of 3-glycidyloxypropyltrimethoxysilane ( ^DYNASYLAN® GLYMO) in a 250ml stainless steel dispersion vessel, and add 20g of ethanol and 20g of titanium dioxide aqueous dispersion (RM 300 WP , TiO ₂ content of 37.8% by weight, obtained from Sachtleben). The liquid was stirred in the dissolver for 5 minutes at a peripheral speed of 1.0 m/s while cooling with water. Thereafter, the dissolver sheet was replaced with a polyamide jacket sheet, and 80 ml of zirconia grinding beads with d = 0.7-1.2 mm were added. The silane- _TiO2 formulation was post-treated for 20 min using the beads thus milled. During the dispersion operation the temperature was raised to 43°C.

This gives a milky beige opalescent liquid with an average particle size distribution of d ₅₀ =80 nm (determined by laser diffraction).

The product was stored at 50°C for 6 months, during which time the system remained stable without significant precipitation.

Example 8

22% by weight ^Aerosil® 380 in ^DYNASYLAN® GLYMO

Put 60.0g of 3-glycidyloxypropyltrimethoxysilane ( ^DYNASYLAN® GLYMO) in a 250ml stainless steel dispersion vessel, and add a solution of 10.0g of deionized water and 0.1g of concentrated acetic acid under stirring (DispermatCV) . The liquid was stirred in the dissolver for 5 minutes at a peripheral speed of 0.8 m/s. This was followed by the initial addition of 20.0 g of nanoscale fumed silica ( ^Aerosil® 380). When 4-5% by weight of Aerosil ^(R) was dispersed in the hydrolyzate, the viscosity increased significantly. During the further addition of Aerosil ^(R) , the speed of the dissolver was gradually increased to a peripheral speed of about 8 m/s. The blending time was approximately 12 minutes. Immediately after complete addition of all ^Aerosil® , dispersion was continued for 2 minutes at a peripheral speed of 25 m/s. The dispersion temperature in the uncooled vessel was raised to 28°C.

This gives a clear, lightly opalescent liquid with a viscosity of <1000 mPa·s. The silane formulation was mixed with 50% deionized water to obtain a low viscosity opalescent fluid. The product was stored at 50°C for 1 month, during which time the system remained stable and no significant precipitation occurred.

The aqueous silane formulation was applied to coated aluminum panels (3105 H24 alloy) with a 6 μm scalpel and the coating was dried at 200°C for 15 minutes. A clear coat shows good resistance to steel wool scratches.

Example 9

25% by weight ^Aerosil® R972 in ^DYNASYLAN® VTMO

170.0 g of vinyltrimethoxysilane ( ^DYNASYLAN® VTMO) was placed in a 500 ml stainless steel dispersion vessel, and a solution of 6.2 g of deionized water and 0.18 g of concentrated hydrochloric acid was added with stirring (Dispermat CV). The liquid was stirred in the dissolver for 5 minutes at a peripheral speed of 0.8 m/s. This was followed by the initial addition of 50.0 g of nanoscale hydrophobic fumed silica ( ^Aerosil® R972). When 4-5% by weight of Aerosil ^(R) was dispersed in the hydrolyzate, the viscosity increased significantly. During the further addition of Aerosil ^(R) , the speed of the dissolver was gradually increased to a peripheral speed of about 8 m/s. Blending time was approximately 21 minutes. Immediately after complete addition of all ^Aerosil® , dispersion was continued for 5 minutes at a peripheral speed of 25 m/s. The dispersion temperature in the uncooled vessel was raised to 39°C.

This gave a yellowish opalescent liquid with a viscosity of 535 mPa·s.

The product was stored at 50°C for 12 months, during which time the system remained stable and no significant precipitation was observed.

comparative example

8% by weight ^Aerosil® 380 in ^DYNASYLAN® MTES

90.0 g of methyltriethoxysilane ( ^DYNASYLAN® MTES) was placed in a 250 ml stainless steel dispersion vessel. This was immediately followed by the incorporation of 8 g of nanoscale fumed silica ( ^Aerosil® 380). The viscosity increased significantly after adding 5 g of ^Aerosil® 380. The speed of the dissolver was increased from 0.8 m/s to 8 m/s and a further 3 g of ^Aerosil® 380 were metered in. This gives a slurry-like mass which is removed from the dispersing vessel with a spatula.

Claims (25)

1. A formulation comprising (i) at least one organoalkoxysilane and/or at least one organoalkoxysiloxane and (ii) at least one inorganic oxide powder and (iii) if If necessary, organic acid or inorganic acid, component (ii) accounts for 5-50% by weight of the formulation, and the viscosity of the formulation is less than 1500 mPa·s. 2. The formulation as claimed in claim 1, comprising as further component (iv) a wetting aid. 3. The formulation according to claim 1 or 2, comprising as further component (v) a diluent or a solvent. 4. The formulation of any one of claims 1-3, wherein the organoalkoxysilane of component (i) has the general formula (I) R _a -Si(OR ¹ ) _4-a (I), wherein the groups R are the same or different, and R is a linear, cyclic, branched or substituted alkyl group having 1 to 18 carbon atoms or an alkenyl group having 2 to 8 carbon atoms, or an aryl group , or alkoxy, or acryloyloxyalkyl or methacryloyloxyalkyl, or epoxyalkyl, or glycidyloxyalkyl, or aminoalkyl, or fluoroalkyl, or mercapto Alkyl, or silylated alkylsulfanyl, or thiocyanatoalkyl, or isocyanatoalkyl, R is a linear, branched or cyclic alkane having ¹ to 6 carbon atoms base, and a is 1 or 2. 5. The formulation according to any one of claims 1-4, wherein the organoalkoxysiloxane of component (i) has the general formula (II) Wherein the group R ² is the same or different, and R ² is a linear, cyclic, branched or substituted alkyl group with 1-18 carbon atoms, an alkenyl group with 2-8 carbon atoms, an aryl acryloxyalkyl or methacryloxyalkyl, glycidyloxyalkyl, epoxyalkyl, fluoroalkyl, aminoalkyl, silylated aminoalkyl, ureidoalkyl group, mercaptoalkyl group, silylated alkylsulfanyl group, thiocyanatoalkyl group, isocyanatoalkyl group or alkoxyl group, R ³ is straight chain, cyclic, Branched or substituted alkyl, ^R is straight chain, cyclic or branched alkyl with 1-6 carbon atoms, x is 0 or 1 or 2, and y is 0 or 1 or 2, provided that ( x+y)<3. 6. The formulation according to any one of claims 1-5, comprising nanoscale powder (ii) having an average particle size ( _d50 ) of less than 1200 nm. 7. The formulation according to any one of claims 1-6, comprising a powder (ii) selected from the group consisting of silica, alumina and transition metal oxides. 8. The formulation as claimed in any one of claims 1 to 7, comprising as a further component at least one reaction product of components (i) and (ii). 9. Formulation according to any one of claims 1 to 8, characterized in that the solids content is up to 90% by weight of the formulation, the individual components of the formulation amounting to 100% by weight. 10. A process for the preparation of a formulation according to at least one of claims 1-9, said process comprising - mixing components (i), (ii) and if necessary (iv), - Addition of 0.001 to <0.8 mol of water per mole of silicon in component (i), if desired together with a catalytic amount of organic or inorganic acid according to component (iii), and dispersing the mixture thoroughly. 11. The method of claim 10, wherein at least one nanoscale inorganic powder (ii) selected from silica, alumina and transition metal oxides is used. 12. The method of claim 10 or 11, wherein at least one organoalkoxysilane selected from the group consisting of the following general formula (I) is used: methyltriethoxysilane, methyltrimethoxysilane, n-propyl Trimethoxysilane, n-Propyltriethoxysilane, Vinyltriethoxysilane, Vinyltrimethoxysilane, 3-Methacryloxypropyltrimethoxysilane, 3-Glycidyloxypropyltrimethoxysilane, 3-Glycidyloxypropyltriethoxysilane, Tridecafluoro-1,1,2,2-tetrahydrooctyltrimethoxy Silane, tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-(n-butyl)-3-aminopropyl Trimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane , bis(3-trimethoxysilylpropyl)amine or 3-mercaptopropyltrimethoxysilane. 13. The method of at least one of claims 9-12, wherein at least one organoalkoxysiloxane of the general formula (II), or a mixture of organoalkoxysiloxanes of the general formula (II), is used, Or a mixture of at least one organoalkoxysilane of the general formula (I) and an organoalkoxysiloxane of the general formula (II). 14. The process as claimed in at least one of claims 9 to 13, wherein 0.05 to 0.5 mol of water per mole of silicon in component (i) is used. 15. The process of at least one of claims 9-14, wherein acetic acid, acrylic acid or maleic acid is used as acid in an amount of 10-3500 ppm by weight, based on the component (i) used in the formulation of the meter. 16. Process according to at least one of claims 9-15, wherein the components used are dispersed at a temperature of 0-80°C. 17. The method according to at least one of claims 9-16, wherein the components used are dispersed for 10-60 minutes. 18. The process as claimed in at least one of claims 9 to 17, wherein the dispersion or formulation thus obtained is worked up at a temperature of 30 to 80° C. with stirring for 1 to 8 hours. 19. The method of at least one of claims 9-18, wherein the formulation is adjusted to pH 2-7 by adding organic or inorganic acids. 20. The formulation according to any one of claims 1-8, obtainable by a process according to at least one of claims 9-19. 21. Use of the preparation according to at least one of claims 1-8 and 20 or the preparation obtained by the method according to any one of claims 9-19 for anti-scratch applications, anti-wear applications , anti-corrosion applications, easy-to-clean applications, barrier applications, used in electronic subsections, used in surface treatment of circuit boards, used as insulating layers, used as release layers, used as surface coatings for solar cells, used as glass fiber glue material or used to uniformly blend nanoscale powders into other types of systems. 22. The preparation of at least one of claims 1-8 and 20 and 21 or the preparation prepared by the method of any one of claims 9-19 in the preparation of plastics, adhesives, sealants, resin-based materials, inks or paint application. 23. The formulation of at least one of claims 1-8 and 20-22 or the formulation obtained by the method of any one of claims 9-19 as a resin-based material, plastic, ink, paint, adhesive or sealant The application of the ingredients of the agent. 24. An article obtainable as claimed in claim 21 or 22. 25. An article as claimed in claim 23 or an article as claimed in claim 24.